The fit is oversized, soft, and a mid weight knit. No need to size up unless you want really oversized.
Sizing guide only - XS6-8 S10-12 M12-14 L16 XL18 - check measurements against a favourite sweater for a better fit.
Chest measurements CM- XS52.5 S55 M57.5 L60 XL62.5 - measured laid flat from 2cm below armpit.
Body length CM - XS62 S63 M64 L65 XL66
Rae wears size Small and is size 10-12